Mars is the fourth planet from the Sun and the seventh largest in the Solar System. A cold, dusty desert world with a thin atmosphere (mostly CO₂), the planet features extinct volcanoes, deep canyons, polar ice caps, and seasons. Mars has two small moons (Phobos and Deimos), a day just over 24 hours long, and a year lasting about 687 Earth days. It is a prime focus of robotic exploration and studies about past water and habitability.
Source: science.nasa.gov
28/10/2015
What happens when a star gets too close to a black hole? Recent observations from Earth-orbiting observatories of an event dubbed ASASSN-14li, in a distant galactic center, appears to be giving one star's harrowing story. Although angularly unresolved, variations in high energy light indicate that some of the star became shredded and reformed into a disk swirling around the dark abyss. In the hypothesized scenario envisioned, a jet formed on the spin axis of the black hole. The innermost part of the disk, colored white, glows most strongly in X-rays and may drive a periodic wind, shown in blue. Future X-ray and ultraviolet observations of stellar disruptions by black holes -- including those in the center of our own galaxy -- hold promise of telling us about the complex dynamics of some of the hottest and highest-gravity places in the universe. Gallery: October's Venus, Jupiter, & Mars Conjunction